In 2006, Rubio traveled around the state holding what he called “idea-raisers,” as opposed to fundraisers, to fill the 100 Ideas book—and to get out and bolster his statewide network of contacts.

Bush wrote the foreword to the book. In it, he recalled “listening with bated breath” to Rubio’s sword ceremony speech. Rubio, meanwhile, wrote the introduction. Of the 100 ideas, he said: “Through my partnership with Speakers Ray Sansom and Dean Cannon, we will spend the next six years striving to move them forward …” He did not mention Bush.

***

In December of 2008, Mel Martinez, Florida’s incumbent junior United States senator, announced he wouldn’t be running for re-election in 2010. Bush considered running for the opening. Rubio deferred. He waited.

“If he were to run, no one would challenge him in the primary—certainly not me,” Rubio would write in his 2012 memoir, An American Son.

But Bush decided against it.

“Not running does not preclude me from being involved in these things, and I will be,” he told the Associated Press in January of 2009. Bush said his brother’s low Oval Office approval ratings hadn’t factored into his thinking. “People know that I’m Jeb Bush, and I don’t think that would have been a problem.”

Rubio entered the race the first week of May. His opponent, of course, was Crist, Bush’s successor, the sitting governor, then hugely popular. Three weeks later, Jeb Bush Jr. endorsed Rubio. The elder Jeb Bush wouldn’t make the same public pronouncement for another year, finally endorsing Rubio in May of 2010, but he nonetheless worked backchannel against Crist. Republican leaders in Florida and Washington got the message, which was, according to lobbyist Ed Rogers, a longtime Bush family ally: “Charlie Crist is not Jeb’s guy—stand by—there’s going to be a Jeb guy.”

“He’s got all the tools,” Bush told National Review in August of 2009. “He’s charismatic and he has the right principles.”

And after Rubio beat Crist so soundly, not once but twice—chasing him from the Republican primary, from the Republican party, then besting him in the general election after he switched to independent status—Bush giddily introduced Rubio at the victory celebration on November 2, 2010, at the swank Biltmore hotel in Coral Gables.

“I’m so proud of Marco,” Bush began. “I’m so proud of his high-voltage energy. I’m so proud of his enthusiasm. I’m so proud of his eloquence. And I’m so proud that he will be a part of a next generation of leaders that will restore America. Marco Rubio is the right man at the right time.”

The possibility of Rubio running for president with Bush running as well loomed for a couple years. People talked.

“I think the general consensus at the time was that Marco was, you know, being a little too big for his britches,” said Mac Stipanovich, a lobbyist in Tallahassee and a Bush backer.

“There was a lot of ‘Wait your turn, boy,’” said Florida Republican strategist Rick Wilson, a Rubio backer. “A lot. A lot, a lot, a lot.”

“When you would talk to Jeb people about Marco running for president against Jeb, they’d be like, ‘Well, there’s no way he’d do that,’” said Schale, the Democratic strategist who ran Obama’s Florida campaign. “Their response was, ‘Well, he wouldn’t do that.’ They were almost indignant about the idea that he’d get in. How dare he?”

“You have to understand their psychology, which is: They’re entitled to this—he’s the rightful heir to this throne,” an inner-circle Rubio confidant said.

Arza, Rubio’s close friend, talked with him in his office in Washington. This was shortly before Rubio made his decision. He was weighing the pros and cons of a run. “If he decided not to run because of Jeb, and you let this thing play out the way it’s played out, Marco would’ve felt, ‘I should’ve ran,’” Arza said. “He goes to me, ‘Look, it would kill me for me to be home watching this unfold, and I didn’t run because of Jeb, and here Jeb is imploding.’”

“I never understood why anybody ever thought that Marco Rubio would do anything other than run for president,” Schale said. “For Marco, it’s just a basic political calculation: Does it make sense or not? And he made the right decision.”

“It’s just how Marco is,” said Fuentes, his former spokesman. “There’s no intent to betray—it’s just that he has a plan in his head and he’s not going to wait. He’ll do what’s best for him.”

“I would not say it surprised me” that Rubio ran, said Goodlette, the former lawmaker, who got to know him by sharing an office suite with Rubio in Tallahassee. “I would have no reason to assume that Marco would have deferred for Jeb.”

Rubio announced he was running last April. Bush camp stewed. Bush hadn’t announced yet, but the signs had been there for months. He was seen as the favorite, with an overwhelming base of financial support. “I think Jeb was deeply hurt,” a supporter said, describing Bush’s mindset like this: “Man, this was a guy I embraced, and this is what he did?”

Cardenas, the influential mutual friend from the very beginning, was asked if he was surprised Rubio ran. “I wasn’t surprised,” he said. “I was disappointed.” He went with Bush.

Asked the same thing, Adam Hasner, a former state representative who is a co-chair for the Rubio campaign in Florida, responded with a flat, declarative answer: “No.”

“Yesterday is over, and we are never going back,” Rubio said in his speech in Miami. “We Americans are proud of our history, but our country has always been about the future. Before us now is the opportunity to author the greatest chapter yet in the amazing story of America. We can’t do that by going back to the leaders and ideas of the past.”

People around the country thought he was talking about Hillary Clinton. People in Florida knew better.

Ever since, from South Florida to Iowa to New Hampshire to South Carolina, from debates to town halls, Bush and Rubio have crossed paths on the campaign trail. Their names have been next to each other in poll after poll, with Rubio’s above Bush’s more often than not, and increasingly so. They have exchanged jabs and barbs. Rubio’s digs typically have been more subtle. “Obviously,” he said in Iowa, “I wouldn’t run for president if I thought somebody else was a better candidate.” He told reporters in New Hampshire he didn’t know where the sword was. “Somewhere at home,” he said. Bush, on the other hand, especially as his cash-flush campaign began to break down, ramped up his assaults on the man some of his donors and staff members describe as “Judas” and diminish as “Marquito.” “I don’t want to attack Marco, but …” Bush has kept saying. He’s young, inexperienced, not as ready. “There is no coronation here,” Bush said, about Rubio, earlier this month on CNN.

And there was the debate in which Bush tried tepidly and ham-handedly to ding Rubio on his spotty Senate attendance. Rubio’s response managed to be simultaneously understated and withering, saying to Bush’s face that “someone has convinced you that attacking me is going to help you,” then turning back to the audience and repeating the line that his campaign—that he—is about “the future.” And there was the debate in which during a commercial break—but still caught on camera—Rubio appeared to move toward Bush to shake his hand and Bush appeared to drop his hand and turn his head.

Bush and Rubio have repeatedly clashed during debates, including a noteworthy exchange during a debate in in Boulder, Colorado, in October. During another, the camera caught an exchange during a commercial break in which Rubio appeared to move toward Bush to shake his hand and Bush appeared to drop his hand and turn his head. | Photo by Justin Sullivan/Getty Images

And their PACs have warred. Bush’s Right to Rise has portrayed Rubio as an untested flip-flopper. Rubio’s Conservative Solutions has painted Bush as old—the succinct title of a recent ad: “Past”—and his campaign as a “train wreck.”

Bush, said Christian Ulvert, a Democratic strategist from Miami, “invested political capital in this young kid, who now is living out his dreams. I think it’s part of Jeb’s downward spiral. He’s campaigning in some ways with a broken heart—and a huge chip on his shoulder. Which is never the best way to campaign.”

“Jeb by his nature worked to build the party and promote young leaders,” Bush spokesman Tim Miller said this week. “I have no sense for how Marco sees the relationship, but Jeb saw helping him in the same way he did many other young Republicans.”

“I don’t have anything to add to the many things that Marco’s said about Jeb in the past,” Rubio spokesman Alex Conant said. In 2012 in his memoir, Rubio called Bush “the man I most admired in Florida politics.”

In Iowa, Rubio did better than expected and Bush did much worse; in New Hampshire, Bush did slightly better than expected and Rubio did worse; now, in South Carolina, Rubio has regained his momentum, buoyed by the coveted endorsement of the state’s popular governor, Nikki Haley. It might have been a fatal blow to Bush.

“It’s hard for me to be lectured by a gifted young guy who thinks going to a committee hearing means you know something about the world,” he told 150 people at a town hall this week. “With all due respect, Senator Rubio, your four years or five years or whatever it is as senator does not match up to my capabilities of understanding how the world works.”

The vast majority of the Republican establishment in Florida has endorsed Bush over Rubio. It hasn’t mattered. Bush’s low polling isn’t budging. He’s running fourth and fifth in South Carolina—trailing Rubio—and lagging in single digits in the national numbers.

“Jeb’s dead,” said Wilson, the Rubio-supporting strategist. “He just hasn’t had to lay down yet.”

Those who know Rubio and Bush—those who have been watching since the sword—wonder what comes next.

“Will their relationship ever be the same as it used to be? Probably not,” said Esteban “Steve” Bovo, a close friend to Rubio, a Miami-Dade commissioner whose youngest son counts Rubio as his godfather.

Wrecked forever? “Forever is a long time,” Stipanovich said. He then started talking about American and Japanese fighter pilots from World War II reuniting in shows of peace half a century hence.

“I don’t think there’s a relationship after this,” a Bush backer said. “But, honestly, there wasn’t a real one to begin with.”

“They’re not, like, brothers or anything,” the Rubio confidant said, “where if they never talked again, it would be this horrible tragedy.”

And if Bush drops out before the Republican primary in Florida on March 15? Will he endorse Rubio in their home state? Will he, even after this campaign, offer up another anointment? “I’m going to bestow to you …”

“He’d have to be very bitter not to do that,” said Diaz de la Portilla, Rubio’s old roommate in Tallahassee. “I think it’s time for Jeb to realize that it’s time to pass the baton.” Again.